1.Field of the Invention
The present invention relates to an information management system, a local computer, a server computer, a computer-readable recording medium recording an information acquisition program and a computer-readable recording medium recording a server program, and more particularly, to an information management system, local computer, server computer, computer-readable recording medium recording an information acquisition program and computer-readable recording medium recording a server program for handling information delivered through a network.
2. Description of the Related Art
As a result of recent rapid popularization of the Internet, it is usually the case that a plurality of servers are started within a server computer to provide a large number of users with innumerable contents such as HTML (Hyper Text Markup Language)-based text, JPEG (Joint Photographic Experts Group) files, GIF (Graphics Interchange Format) files, and sound files. Image files like JPEG files and sound files have large file size as compared with text files, and thus take time to be transmitted. Consequently, the amount of information transmitted over lines drastically increases, causing overloading of lines.
To avoid such line congestion, contents once accessed are cached in a local medium (such as a hard disk unit). This permits the cached contents to be read out from the local medium when accessed again, so that the amount of information transmitted over communication lines can be reduced.
The method of caching contents is, however, associated with a problem that information must always be transferred from a server when accessed for the first time. Also, cached data is usually kept only for a limited term, and therefore, access after expiry of the term is influenced all the same by the capacity of transmission lines.
Meanwhile, some contents on the Internet are updated almost every day, while others need not be updated for a fixed period of time. For example, contents such as a list of participants in some meeting scarcely need to be updated after the meeting schedule and the participants are fixed until the end of the meeting. Moreover, if particular members alone are to attend such a meeting, it is enough that the contents about the meeting can be viewed only by the members concerned.
Such specific contents may therefore be recorded in CD-ROMs (Compact Disk Read Only Memories) and the CD-ROMs may be distributed to those who require the contents. In this case, however, when the contents are recorded in the media, inter-content links must be rewritten. Specifically, where HTML files exist in a server, links and image files to be shown in-line are designated by URLs (Uniform Resource Locators) assigned to respective designated files on the server. Accordingly, in the case of storing, in a CD-ROM, contents including linked files and image files to be shown in-line, the location of files to be designated should be the local medium. To permit the local medium to be accessed as the target of links, the URL specifications need to be rewritten so as to include the local name. Rewriting the URLs of all HTML files, however, consumes much labor and time.
Taking the above into consideration, an object of the present invention is to provide an information management system which records, directly in a medium, contents on a server that need not be updated for a fixed period of time and which permits desired contents in a local device to be accessed by the same operation procedure as that for accessing the server storing the contents.
To accomplish the above object, according to the present invention, there is provided an information management system for management of information delivered through a network, comprising:
a server computer including delivery information storing means for storing delivery information to be delivered through the network and a server-side control file in which attribute information of the delivery information is registered, and a server for delivering, in response to a request, information stored in the delivery information storing means; and
a local computer including duplicate information storing means for storing duplicate information corresponding to the delivery information in the delivery information storing means and a local-side control file in which are registered location information indicative of a location within the delivery information storing means where the duplicate information existed and attribute information of the duplicate information, and request relaying means, responsive to a request to acquire the delivery information stored in the delivery information storing means, for acquiring the server-side control file and the local-side control file, comparing the attribute information of the requested delivery information with the attribute information of the duplicate information corresponding to the requested delivery information, and determining information to be acquired in accordance with a result of comparison.